Changing Themes (Mac & iOS)

How do I change themes?

iOS

Open Twitterrific's sidebar and press the theme button (the
center button at the bottom of the panel). Here, you can change to
the dark or light theme, select a font, change the font, avatar and
line spacing size, and set the in-app brightness. You can also use
a two-fingered swipe gesture to instantly change from the dark to
light theme and vice versa.

Mac

Press command-', to open the preferences panel and then click
the General tab. Select the theme you would like to use from the
Appearance selection menu to see the results in real time on the
desktop.